Colorado investigators are exploring the possibility that Tom Clements, the Department of Corrections head, was murdered because he denied a request by a Saudi national to finish his sentence in his homeland.

Clements, 58, was the executive director of the Colorado Department of Corrections and oversaw the state prison and parole system. He was shot and killed Tuesday night after opening the front door at his home in Monument, near Colorado Springs. Police were still searching for his killer as of Thursday morning.

While police have yet to determine a motive and identify a suspect in Clements’ murder, they are pursuing the connection between the transfer request and the killing, Denver television station KDVR reported.

The Saudi national, Homaidan al-Turki, was convicted of unlawful sexual contact by use of force in 2006 for sexually assaulting his housekeeper and keeping her as a slave for four years, KDVR reported.

Al-Turki appealed to the prison system to be transferred to Saudi Arabia and serve his life sentence there, but the request was denied by Clements last week.

“I have decided not to support your request for transfer to Saudi Arabia at this time,” Clements wrote in his decision.

Saudi officials were so angered over al-Turki’s conviction that they became involved in the case. Colorado state Attorney General John Suthers met with Saudi King Abdullah, Crown Prince Sultan and al-Turki’s family in Saudi Arabia, KDVR reported.

Police have all but ruled out robbery as a motive for Clements’ murder, the Denver Post reported.

"There is no evidence of a home invasion," Lt. Jeff Kramer, spokesman for the El Paso County Sheriff’s office, told the newspaper.

Kramer said police are considering whether Clements’ job was connected to the murder.

“We know of his position and realize that it is a possible motive for a crime such as this," Kramer said.

Clements was killed a day before Gov. John Hickenlooper signed new gun legislation, including limiting ammunition magazine capacity and extending background checks for gun purchases in Colorado. Clements was in favor of the legislation, which was inspired by a mass shooting at an Aurora movie theater.